Unlike physicists and chemists, historians have been unable to formulate grand equations or immutable laws. The trends of history, it would seem, are outside the scope of reproducible science.

But a new discipline called "cliodynamics" is looking to change all that. After studying and mapping key indicators of history, University of Connecticut's Peter Turchin believes that he's detected consistent cycles in human history — cycles that he argues could actually help us predict the future.

Turchin, a professor of population dynamics, named the new discipline after Clio, the ancient Greek muse of history. He, along with other colleagues, are working to apply scientific methods to history by analyzing broad social forces that impact and shape all human societies.

Writing in Nature, Laura Spinney describes how Turchin's analysis relies on four main variables: population numbers, social structure, state strength, and political instability. She elaborates:

Each variable is measured in several ways. Social structure, for example, relies on factors such as health inequality - measured using proxies including quantitative data on life expectancies - and wealth inequality, measured by the ratio of the largest fortune to the median wage. Choosing appropriate proxies can be a challenge, because relevant data are often hard to find. No proxy is perfect, the researchers concede. But they try to minimize the problem by choosing at least two proxies for each variable.

Once this is done, Turchen turns to historical documentation in an effort to detect patterns — what he contends he was able to do. Spinney describes what he came up with:

When Turchin refined the concept of cliodynamics with two colleagues - Sergey Nefedov of the Institute of History and Archaeology in Yekaterinburg, Russia, and Andrey Korotayev of the Russian State University for the Humanities in Moscow - the researchers found that two trends dominate the data on political instability. The first, which they call the secular cycle, extends over two to three centuries. It starts with a relatively egalitarian society, in which supply and demand for labour roughly balance out. In time, the population grows, labour supply outstrips demand, elites form and the living standards of the poorest fall. At a certain point, the society becomes top-heavy with elites, who start fighting for power. Political instability ensues and leads to collapse, and the cycle begins again.

Superimposed on that secular trend, the researchers observe a shorter cycle that spans 50 years - roughly two generations. Turchin calls this the fathers-and-sons cycle: the father responds violently to a perceived social injustice; the son lives with the miserable legacy of the resulting conflict and abstains; the third generation begins again. Turchin likens this cycle to a forest fire that ignites and burns out, until a sufficient amount of underbrush accumulates and the cycle recommences.

Accordingly to Turchin, these cycles fit patterns of instability across Europe and Asia from the fifth century BC onwards. He sees these cycles in the history of Roman Republic straight through to the timing of last year's uprising in Egypt.

Spinney's article at Nature is a bit of a long read but totally worth it. This is a fascinating new area, one that, along with computational social science, could represent the future of both history and social studies in general. But as Spinney aptly points out, the new field is not without its critics. Find out what she means by going here.